K8S学习笔记之二进制的方式创建一个Kubernetes集群
0x00 单节点搭建和简述
minikube
Minikube是一个工具，可以在本地快速运行一个单点的Kubernetes，尝试Kubernetes或日常开发的用户使用。不能用于生产环境。
官方地址：https://kubernetes.io/docs/setup/minikube/
kubeadm
Kubeadm也是一个工具，提供kubeadm init和kubeadm join，用于快速部署Kubernetes集群。
官方地址：https://kubernetes.io/docs/reference/setup-tools/kubeadm/kubeadm/
二进制包
从官方下载发行版的二进制包，手动部署每个组件，组成Kubernetes集群，https://kubernetes.io/docs/home/。
官方也提供了一个互动测试环境供大家玩耍：https://kubernetes.io/cn/docs/tutorials/kubernetes-basics/cluster-interactive/
生产环境中部署Kubernetes集群，只有Kubeadm和二进制包可选，Kubeadm降低部署门槛，但屏蔽了很多细节，遇到问题很难排查。我们这里使用二进制包部署Kubernetes集群，我也是推荐大家使用这种方式，虽然手动部署麻烦点，但学习很多工作原理，更有利于后期维护。
在部署之前，有个职场情况给大家分享下，咱们是为公司打工，拿着老板的工资，在其位谋其职，一定要突出自己的工作，不要做幕后工作者，也就是说做的任何事都尽量量化，让领导知道。
一个正确的工作方式应该是这样的：
# 1.梳理现状，发现问题； # 2.分析问题大致解决方案； # 3.如果有多种方案，总结利弊，向上级汇报； # 4.如果需要部门协作，开会讨论，确定可行性方案，立项； # 5.会议立项后，制定具体执行方案； # 6.评审通过后，实施； # 7.最后项目报告。
0x01 Kubernetes集群部署架构规划
软件环境
硬件环境
Kubernetes 架构图
Kubernetes工作流程
0x02 部署Etcd集群
在Master节点操作，使用cfssl来生成自签证书，先下载cfssl工具，下面操作请新建一个文件夹，在文件夹内操作。
wget https://pkg.cfssl.org/R1.2/cfssl_linux-amd64 wget https://pkg.cfssl.org/R1.2/cfssljson_linux-amd64 wget https://pkg.cfssl.org/R1.2/cfssl-certinfo_linux-amd64 chmod +x cfssl_linux-amd64 cfssljson_linux-amd64 cfssl-certinfo_linux-amd64 mv cfssl_linux-amd64 /usr/local/bin/cfssl mv cfssljson_linux-amd64 /usr/local/bin/cfssljson mv cfssl-certinfo_linux-amd64 /usr/bin/cfssl-certinfo
2.1 生成Etcd证书
在Master节点操作，创建以下三个文件
# cat ca-config.json { "signing": { "default": { "expiry": "87600h" }, "profiles": { "www": { "expiry": "87600h", "usages": [ "signing", "key encipherment", "server auth", "client auth" ] } } } } # cat ca-csr.json { "CN": "etcd CA", "key": { "algo": "rsa", "size": 2048 }, "names": [ { "C": "CN", "L": "Beijing", "ST": "Beijing" } ] } # cat server-csr.json { "CN": "etcd", "hosts": [ "192.168.26.135", "192.168.26.136", "192.168.26.137" ], "key": { "algo": "rsa", "size": 2048 }, "names": [ { "C": "CN", "L": "BeiJing", "ST": "BeiJing" } ] }
生成证书
cfssl gencert -initca ca-csr.json | cfssljson -bare ca - cfssl gencert -ca=ca.pem -ca-key=ca-key.pem -config=ca-config.json -profile=www server-csr.json | cfssljson -bare server # ls *pem ca-key.pem ca.pem server-key.pem server.pem
2.2 安装Etcd
以下操作需要在三个节点上操作，二进制包下载地址：https://github.com/coreos/etcd/releases/tag/v3.2.12
# 以下部署步骤在规划的三个etcd节点操作一样，唯一不同的是etcd配置文件中的服务器IP要写当前主机的IP：
解压二进制包
mkdir /opt/etcd/{bin,cfg,ssl} -p
tar zxvf etcd-v3.2.12-linux-amd64.tar.gz
mv etcd-v3.2.12-linux-amd64/{etcd,etcdctl} /opt/etcd/bin/
创建etcd配置文件，注意在不同节点上操作，要替换为各个节点的IP，此处是135节点的示例
# vim /opt/etcd/cfg/etcd #[Member] ETCD_NAME="etcd01" ETCD_DATA_DIR="/var/lib/etcd/default.etcd" ETCD_LISTEN_PEER_URLS="https://192.168.26.135:2380" ETCD_LISTEN_CLIENT_URLS="https://192.168.26.135:2379" #[Clustering] ETCD_INITIAL_ADVERTISE_PEER_URLS="https://192.168.26.135:2380" ETCD_ADVERTISE_CLIENT_URLS="https://192.168.26.135:2379" ETCD_INITIAL_CLUSTER="etcd01=https://192.168.26.135:2380,etcd02=https://192.168.26.136:2380,etcd03=https://192.168.26.137:2380" ETCD_INITIAL_CLUSTER_TOKEN="etcd-cluster" ETCD_INITIAL_CLUSTER_STATE="new"
# ETCD_NAME 节点名称 # ETCD_DATA_DIR 数据目录 # ETCD_LISTEN_PEER_URLS 集群通信监听地址 # ETCD_LISTEN_CLIENT_URLS 客户端访问监听地址 # ETCD_INITIAL_ADVERTISE_PEER_URLS 集群通告地址 # ETCD_ADVERTISE_CLIENT_URLS 客户端通告地址 # ETCD_INITIAL_CLUSTER 集群节点地址 # ETCD_INITIAL_CLUSTER_TOKEN 集群Token # ETCD_INITIAL_CLUSTER_STATE 加入集群的当前状态，new是新集群，existing表示加入已有集群
创建systemd管理etcd，在三个节点上都要操作
# vim /usr/lib/systemd/system/etcd.service [Unit] Description=Etcd Server After=network.target After=network-online.target Wants=network-online.target [Service] Type=notify EnvironmentFile=/opt/etcd/cfg/etcd ExecStart=/opt/etcd/bin/etcd \ --name=${ETCD_NAME} \ --data-dir=${ETCD_DATA_DIR} \ --listen-peer-urls=${ETCD_LISTEN_PEER_URLS} \ --listen-client-urls=${ETCD_LISTEN_CLIENT_URLS},http://127.0.0.1:2379 \ --advertise-client-urls=${ETCD_ADVERTISE_CLIENT_URLS} \ --initial-advertise-peer-urls=${ETCD_INITIAL_ADVERTISE_PEER_URLS} \ --initial-cluster=${ETCD_INITIAL_CLUSTER} \ --initial-cluster-token=${ETCD_INITIAL_CLUSTER_TOKEN} \ --initial-cluster-state=new \ --cert-file=/opt/etcd/ssl/server.pem \ --key-file=/opt/etcd/ssl/server-key.pem \ --peer-cert-file=/opt/etcd/ssl/server.pem \ --peer-key-file=/opt/etcd/ssl/server-key.pem \ --trusted-ca-file=/opt/etcd/ssl/ca.pem \ --peer-trusted-ca-file=/opt/etcd/ssl/ca.pem Restart=on-failure LimitNOFILE=65536 [Install] WantedBy=multi-user.target
把新建文件夹中的证书拷贝到各个节点如下的位置，每个节点的这个文件夹下都要有这些.pem证书，可以使用scp跨主机传输
cp ca*pem server*pem /opt/etcd/ssl
启动并设置开启启动
systemctl start etcd
systemctl enable etcd
都部署完成后，检查etcd集群状态（注意正确填写.pem证书的路径）
# /opt/etcd/bin/etcdctl \ --ca-file=ca.pem --cert-file=server.pem --key-file=server-key.pem \ --endpoints="https://192.168.26.135:2379,https://192.168.26.136:2379,https://192.168.26.137:2379" \ cluster-health member 18218cfabd4e0dea is healthy: got healthy result from https://192.168.26.135:2379 member 541c1c40994c939b is healthy: got healthy result from https://192.168.26.136:2379 member a342ea2798d20705 is healthy: got healthy result from https://192.168.26.137:2379 cluster is healthy
如果输出上面信息，就说明集群部署成功。如果有问题第一步先看日志：/var/log/message 或 journalctl -u etcd
0x03 在Node节点安装Docker
在两台node节点安装
yum install -y yum-utils device-mapper-persistent-data lvm2 yum-config-manager \ --add-repo \ https://download.docker.com/linux/centos/docker-ce.repo yum install docker-ce -y curl -sSL https://get.daocloud.io/daotools/set_mirror.sh | sh -s http://bc437cce.m.daocloud.io systemctl start docker systemctl enable docker
0x04 部署Flannel网络
Flannel工作原理
Falnnel要用etcd存储自身一个子网信息，所以要保证能成功连接Etcd，写入预定义子网段，在任一个节点执行如下命令即可
# /opt/etcd/bin/etcdctl \ --ca-file=ca.pem --cert-file=server.pem --key-file=server-key.pem \ --endpoints="https://192.168.26.135:2379,https://192.168.26.136:2379,https://192.168.26.137:2379" \ set /coreos.com/network/config '{ "Network": "172.17.0.0/16", "Backend": {"Type": "vxlan"}}'
以下部署步骤在规划的每个node节点都操作
下载二进制包
wget https://github.com/coreos/flannel/releases/download/v0.10.0/flannel-v0.10.0-linux-amd64.tar.gz tar zxvf flannel-v0.10.0-linux-amd64.tar.gz mv flanneld mk-docker-opts.sh /opt/kubernetes/bin
配置Flannel
# vim /opt/kubernetes/cfg/flanneld FLANNEL_OPTIONS="--etcd-endpoints=https://192.168.26.135:2379,https://192.168.26.136:2379,https://192.168.26.137:2379 -etcd-cafile=/opt/etcd/ssl/ca.pem -etcd-certfile=/opt/etcd/ssl/server.pem -etcd-keyfile=/opt/etcd/ssl/server-key.pem"
创建systemd管理Flannel
# vim /usr/lib/systemd/system/flanneld.service [Unit] Description=Flanneld overlay address etcd agent After=network-online.target network.target Before=docker.service [Service] Type=notify EnvironmentFile=/opt/kubernetes/cfg/flanneld ExecStart=/opt/kubernetes/bin/flanneld --ip-masq $FLANNEL_OPTIONS ExecStartPost=/opt/kubernetes/bin/mk-docker-opts.sh -k DOCKER_NETWORK_OPTIONS -d /run/flannel/subnet.env Restart=on-failure [Install] WantedBy=multi-user.target
配置Docker启动指定子网段
# vim /usr/lib/systemd/system/docker.service [Unit] Description=Docker Application Container Engine Documentation=https://docs.docker.com After=network-online.target firewalld.service Wants=network-online.target [Service] Type=notify EnvironmentFile=/run/flannel/subnet.env ExecStart=/usr/bin/dockerd $DOCKER_NETWORK_OPTIONS ExecReload=/bin/kill -s HUP $MAINPID LimitNOFILE=infinity LimitNPROC=infinity LimitCORE=infinity TimeoutStartSec=0 Delegate=yes KillMode=process Restart=on-failure StartLimitBurst=3 StartLimitInterval=60s [Install] WantedBy=multi-user.target
重启flannel和docker
# systemctl daemon-reload # systemctl start flanneld # systemctl enable flanneld # systemctl restart docker
检查是否生效
# ps -ef |grep docker root 20941 1 1 Jun28 ? 09:15:34 /usr/bin/dockerd --bip=172.17.34.1/24 --ip-masq=false --mtu=1450 # ip addr 3607: flannel.1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1450 qdisc noqueue state UNKNOWN link/ether 8a:2e:3d:09:dd:82 brd ff:ff:ff:ff:ff:ff inet 172.17.34.0/32 scope global flannel.1 valid_lft forever preferred_lft forever 3608: docker0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1450 qdisc noqueue state UP link/ether 02:42:31:8f:d3:02 brd ff:ff:ff:ff:ff:ff inet 172.17.34.1/24 brd 172.17.34.255 scope global docker0 valid_lft forever preferred_lft forever inet6 fe80::42:31ff:fe8f:d302/64 scope link valid_lft forever preferred_lft forever
确保docker0与flannel.1在同一网段。
测试不同节点互通，在当前节点访问另一个Node节点docker0
IP：
# ping 172.17.58.1 PING 172.17.58.1 (172.17.58.1) 56(84) bytes of data. 64 bytes from 172.17.58.1: icmp_seq=1 ttl=64 time=0.263 ms 64 bytes from 172.17.58.1: icmp_seq=2 ttl=64 time=0.204 ms
如果能通说明Flannel部署成功。如果不通检查下日志：journalctl -u flannel
0x05 在Master节点部署组件
在部署Kubernetes之前一定要确保etcd、flannel、docker是正常工作的，否则先解决问题再继续。
5.1 生成证书
在Master的一个新建文件夹内进行如下操作.
创建CA证书
# vim ca-config.json { "signing": { "default": { "expiry": "87600h" }, "profiles": { "kubernetes": { "expiry": "87600h", "usages": [ "signing", "key encipherment", "server auth", "client auth" ] } } } } # vim ca-csr.json { "CN": "kubernetes", "key": { "algo": "rsa", "size": 2048 }, "names": [ { "C": "CN", "L": "Beijing", "ST": "Beijing", "O": "k8s", "OU": "System" } ] } # cfssl gencert -initca ca-csr.json | cfssljson -bare ca -
生成apiserver证书
# vim server-csr.json { "CN": "kubernetes", "hosts": [ "10.0.0.1", "127.0.0.1", "192.168.26.135", "192.168.26.136", "192.168.26.137", "kubernetes", "kubernetes.default", "kubernetes.default.svc", "kubernetes.default.svc.cluster", "kubernetes.default.svc.cluster.local" ], "key": { "algo": "rsa", "size": 2048 }, "names": [ { "C": "CN", "L": "BeiJing", "ST": "BeiJing", "O": "k8s", "OU": "System" } ] } # cfssl gencert -ca=ca.pem -ca-key=ca-key.pem -config=ca-config.json -profile=kubernetes server-csr.json | cfssljson -bare server
生成kube-proxy证书
# vim kube-proxy-csr.json { "CN": "system:kube-proxy", "hosts": [], "key": { "algo": "rsa", "size": 2048 }, "names": [ { "C": "CN", "L": "BeiJing", "ST": "BeiJing", "O": "k8s", "OU": "System" } ] } # cfssl gencert -ca=ca.pem -ca-key=ca-key.pem -config=ca-config.json -profile=kubernetes kube-proxy-csr.json | cfssljson -bare kube-proxy
最终生成以下证书文件
# ls *pem ca-key.pem ca.pem kube-proxy-key.pem kube-proxy.pem server-key.pem server.pem
5.2 部署apiserver组件
下载二进制包：https://github.com/kubernetes/kubernetes/blob/master/CHANGELOG-1.11.md
下载这个包（kubernetes-server-linux-amd64.tar.gz）就够了，包含了所需的所有组件。
# mkdir /opt/kubernetes/{bin,cfg,ssl} -p # tar zxvf kubernetes-server-linux-amd64.tar.gz # cd kubernetes/server/bin # cp kube-apiserver kube-scheduler kube-controller-manager kubectl /opt/kubernetes/bin
新建token文件
# vim /opt/kubernetes/cfg/token.csv 674c457d4dcf2eefe4920d7dbb6b0ddc,kubelet-bootstrap,10001,"system:kubelet-bootstrap"
# $0：随机字符串，自己可生成 # $1：用户名 # $2：UID # $3：用户组
创建apiserver配置文件
# vim /opt/kubernetes/cfg/kube-apiserver KUBE_APISERVER_OPTS="--logtostderr=true \ --v=4 \ --etcd-servers=https://192.168.26.135:2379,https://192.168.26.136:2379,https://192.168.26.137:2379 \ --bind-address=192.168.26.135 \ --secure-port=6443 \ --advertise-address=192.168.26.135\ --allow-privileged=true \ --service-cluster-ip-range=10.0.0.0/24 \ --enable-admission-plugins=NamespaceLifecycle,LimitRanger,ServiceAccount,ResourceQuota,NodeRestriction \ --authorization-mode=RBAC,Node \ --enable-bootstrap-token-auth \ --token-auth-file=/opt/kubernetes/cfg/token.csv \ --service-node-port-range=30000-50000 \ --tls-cert-file=/opt/kubernetes/ssl/server.pem \ --tls-private-key-file=/opt/kubernetes/ssl/server-key.pem \ --client-ca-file=/opt/kubernetes/ssl/ca.pem \ --service-account-key-file=/opt/kubernetes/ssl/ca-key.pem \ --etcd-cafile=/opt/etcd/ssl/ca.pem \ --etcd-certfile=/opt/etcd/ssl/server.pem \ --etcd-keyfile=/opt/etcd/ssl/server-key.pem"
注意填写证书的路径，并且确保etcd是正常运行。
# --logtostderr 启用日志 # ---v 日志等级 # --etcd-servers etcd集群地址 # --bind-address 监听地址 # --secure-port https安全端口 # --advertise-address 集群通告地址 # --allow-privileged 启用授权 # --service-cluster-ip-range Service虚拟IP地址段 # --enable-admission-plugins 准入控制模块 # --authorization-mode 认证授权，启用RBAC授权和节点自管理 # --enable-bootstrap-token-auth 启用TLS bootstrap功能，后面会讲到 # --token-auth-file token文件 # --service-node-port-range Service Node类型默认分配端口范围
创建systemd管理apiserver
# vim /usr/lib/systemd/system/kube-apiserver.service [Unit] Description=Kubernetes API Server Documentation=https://github.com/kubernetes/kubernetes [Service] EnvironmentFile=-/opt/kubernetes/cfg/kube-apiserver ExecStart=/opt/kubernetes/bin/kube-apiserver $KUBE_APISERVER_OPTS Restart=on-failure [Install] WantedBy=multi-user.target
# systemctl daemon-reload # systemctl enable kube-apiserver # systemctl restart kube-apiserver
5.3 部署schduler组件
创建schduler配置文件
# vim /opt/kubernetes/cfg/kube-scheduler KUBE_SCHEDULER_OPTS="--logtostderr=true \ --v=4 \ --master=127.0.0.1:8080 \ --leader-elect"
# --master 连接本地apiserver # --leader-elect 当该组件启动多个时，自动选举（HA）
systemd管理schduler组件
# vim /usr/lib/systemd/system/kube-scheduler.service [Unit] Description=Kubernetes Scheduler Documentation=https://github.com/kubernetes/kubernetes [Service] EnvironmentFile=-/opt/kubernetes/cfg/kube-scheduler ExecStart=/opt/kubernetes/bin/kube-scheduler $KUBE_SCHEDULER_OPTS Restart=on-failure [Install] WantedBy=multi-user.target
# systemctl daemon-reload # systemctl enable kube-scheduler # systemctl restart kube-scheduler
5.4 部署controller-manager组件
创建controller-manager配置文件
# vim /opt/kubernetes/cfg/kube-controller-manager KUBE_CONTROLLER_MANAGER_OPTS="--logtostderr=true \ --v=4 \ --master=127.0.0.1:8080 \ --leader-elect=true \ --address=127.0.0.1 \ --service-cluster-ip-range=10.0.0.0/24 \ --cluster-name=kubernetes \ --cluster-signing-cert-file=/opt/kubernetes/ssl/ca.pem \ --cluster-signing-key-file=/opt/kubernetes/ssl/ca-key.pem \ --root-ca-file=/opt/kubernetes/ssl/ca.pem \ --service-account-private-key-file=/opt/kubernetes/ssl/ca-key.pem"
systemd管理controller-manager组件
# vim /usr/lib/systemd/system/kube-controller-manager.service [Unit] Description=Kubernetes Controller Manager Documentation=https://github.com/kubernetes/kubernetes [Service] EnvironmentFile=-/opt/kubernetes/cfg/kube-controller-manager ExecStart=/opt/kubernetes/bin/kube-controller-manager $KUBE_CONTROLLER_MANAGER_OPTS Restart=on-failure [Install] WantedBy=multi-user.target
# systemctl daemon-reload # systemctl enable kube-controller-manager # systemctl restart kube-controller-manager
所有组件都已经启动成功，通过kubectl工具查看当前集群组件状态：
# /opt/kubernetes/bin/kubectl get cs NAME STATUS MESSAGE ERROR scheduler Healthy ok etcd-0 Healthy {"health":"true"} etcd-2 Healthy {"health":"true"} etcd-1 Healthy {"health":"true"} controller-manager Healthy ok
0x06 在Node节点部署组件
Master apiserver启用TLS认证后，Node节点kubelet组件想要加入集群，必须使用CA签发的有效证书才能与apiserver通信，当Node节点很多时，签署证书是一件很繁琐的事情，因此有了TLS Bootstrapping机制，kubelet会以一个低权限用户自动向apiserver申请证书，kubelet的证书由apiserver动态签署。
认证大致工作流程如图所示：
6.1 将kubelet-bootstrap用户绑定到系统集群角色
在Master‘节点执行此命令
kubectl create clusterrolebinding kubelet-bootstrap \ --clusterrole=system:node-bootstrapper \ --user=kubelet-bootstrap
6.2 创建kubeconfig文件
在Master节点执行如下命令，注意.pem文件的路径
在生成kubernetes证书的目录下执行以下命令生成kubeconfig文件： # 创建kubelet bootstrapping kubeconfig # 指定apiserver 内网负载均衡地址 KUBE_APISERVER="https://192.168.26.135:6443" BOOTSTRAP_TOKEN=674c457d4dcf2eefe4920d7dbb6b0ddc # 设置集群参数 kubectl config set-cluster kubernetes \ --certificate-authority=./ca.pem \ --embed-certs=true \ --server=${KUBE_APISERVER} \ --kubeconfig=bootstrap.kubeconfig # 设置客户端认证参数 kubectl config set-credentials kubelet-bootstrap \ --token=${BOOTSTRAP_TOKEN} \ --kubeconfig=bootstrap.kubeconfig # 设置上下文参数 kubectl config set-context default \ --cluster=kubernetes \ --user=kubelet-bootstrap \ --kubeconfig=bootstrap.kubeconfig # 设置默认上下文 kubectl config use-context default --kubeconfig=bootstrap.kubeconfig #---------------------- # 创建kube-proxy kubeconfig文件 kubectl config set-cluster kubernetes \ --certificate-authority=./ca.pem \ --embed-certs=true \ --server=${KUBE_APISERVER} \ --kubeconfig=kube-proxy.kubeconfig kubectl config set-credentials kube-proxy \ --client-certificate=./kube-proxy.pem \ --client-key=./kube-proxy-key.pem \ --embed-certs=true \ --kubeconfig=kube-proxy.kubeconfig kubectl config set-context default \ --cluster=kubernetes \ --user=kube-proxy \ --kubeconfig=kube-proxy.kubeconfig kubectl config use-context default --kubeconfig=kube-proxy.kubeconfig # ls bootstrap.kubeconfig kube-proxy.kubeconfig
将这两个文件拷贝到Node节点/opt/kubernetes/cfg目录下，可使用scp命令。
6.3 部署kubelet组件
将前面下载的二进制包server>>bin文件夹下的kubelet和kube-proxy拷贝到各个node节点的/opt/kubernetes/bin目录下，可使用scp命令。
创建kubelet配置文件，如下是在node节点192.168.26.136上的示例
# vim /opt/kubernetes/cfg/kubelet KUBELET_OPTS="--logtostderr=true \ --v=4 \ --hostname-override=192.168.26.136 \ --kubeconfig=/opt/kubernetes/cfg/kubelet.kubeconfig \ --bootstrap-kubeconfig=/opt/kubernetes/cfg/bootstrap.kubeconfig \ --config=/opt/kubernetes/cfg/kubelet.config \ --cert-dir=/opt/kubernetes/ssl \ --pod-infra-container-image=registry.cn-hangzhou.aliyuncs.com/google-containers/pause-amd64:3.0"
# --hostname-override 在集群中显示的主机名 # --kubeconfig 指定kubeconfig文件位置，会自动生成 # --bootstrap-kubeconfig 指定刚才生成的bootstrap.kubeconfig文件 # --cert-dir 颁发证书存放位置 # --pod-infra-container-image 管理Pod网络的镜像
其中/opt/kubernetes/cfg/kubelet.config配置文件如下：
# vim /opt/kubernetes/cfg/kubelet.config kind: KubeletConfiguration apiVersion: kubelet.config.k8s.io/v1beta1 address: 192.168.26.136 port: 10250 readOnlyPort: 10255 cgroupDriver: cgroupfs clusterDNS: ["10.0.0.2"] clusterDomain: cluster.local. failSwapOn: false authentication: anonymous: enabled: true webhook: enabled: false
systemd管理kubelet组件
# vim /usr/lib/systemd/system/kubelet.service [Unit] Description=Kubernetes Kubelet After=docker.service Requires=docker.service [Service] EnvironmentFile=/opt/kubernetes/cfg/kubelet ExecStart=/opt/kubernetes/bin/kubelet $KUBELET_OPTS Restart=on-failure KillMode=process [Install] WantedBy=multi-user.target
# systemctl daemon-reload # systemctl enable kubelet # systemctl restart kubelet
在Master审批Node加入集群：
启动后还没加入到集群中，需要手动允许该节点才可以。
在Master节点查看请求签名的Node：
# kubectl get csr # kubectl certificate approve XXXXPOD ID # kubectl get node
systemd管理kube-proxy组件
# vim /usr/lib/systemd/system/kube-proxy.service [Unit] Description=Kubernetes Proxy After=network.target [Service] EnvironmentFile=-/opt/kubernetes/cfg/kube-proxy ExecStart=/opt/kubernetes/bin/kube-proxy $KUBE_PROXY_OPTS Restart=on-failure [Install] WantedBy=multi-user.target
# systemctl daemon-reload # systemctl enable kube-proxy # systemctl restart kube-proxy
0x07 查看集群状态
# kubectl get node NAME STATUS ROLES AGE VERSION 192.168.26.136 Ready <none> 28d v1.11.0 192.168.26.137 Ready <none> 28d v1.11.0 # kubectl get cs NAME STATUS MESSAGE ERROR controller-manager Healthy ok scheduler Healthy ok etcd-2 Healthy {"health":"true"} etcd-1 Healthy {"health":"true"} etcd-0 Healthy {"health":"true"}
0x08 运行一个测试示例
创建一个Nginx Web，判断集群是否正常工作
# kubectl run nginx --image=nginx --replicas=3 # kubectl expose deployment nginx --port=88 --target-port=80 --type=NodePort
查看Pod，Service
# kubectl get pods NAME READY STATUS RESTARTS AGE nginx-64f497f8fd-fjgt2 1/1 Running 3 28d nginx-64f497f8fd-gmstq 1/1 Running 3 28d nginx-64f497f8fd-q6wk9 1/1 Running 3 28d # kubectl get svc NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE kubernetes ClusterIP 10.0.0.1 <none> 443/TCP 28d nginx NodePort 10.0.0.175 <none> 88:38696/TCP 28d
打开浏览器输入：http://192.168.26.136:38696
恭喜你，集群部署成功！
0x09 部署Dashboard(UI)
部署UI有三个文件：
- dashboard-deployment.yaml # 部署Pod，提供Web服务
- dashboard-rbac.yaml # 授权访问apiserver获取信息
- dashboard-service.yaml # 发布服务，提供对外访问
# vim dashboard-deployment.yaml apiVersion: apps/v1beta2 kind: Deployment metadata: name: kubernetes-dashboard namespace: kube-system labels: k8s-app: kubernetes-dashboard kubernetes.io/cluster-service: "true" addonmanager.kubernetes.io/mode: Reconcile spec: selector: matchLabels: k8s-app: kubernetes-dashboard template: metadata: labels: k8s-app: kubernetes-dashboard annotations: scheduler.alpha.kubernetes.io/critical-pod: '' spec: serviceAccountName: kubernetes-dashboard containers: - name: kubernetes-dashboard image: registry.cn-hangzhou.aliyuncs.com/kube_containers/kubernetes-dashboard-amd64:v1.8.1 resources: limits: cpu: 100m memory: 300Mi requests: cpu: 100m memory: 100Mi ports: - containerPort: 9090 protocol: TCP livenessProbe: httpGet: scheme: HTTP path: / port: 9090 initialDelaySeconds: 30 timeoutSeconds: 30 tolerations: - key: "CriticalAddonsOnly" operator: "Exists" # vim dashboard-rbac.yaml apiVersion: v1 kind: ServiceAccount metadata: labels: k8s-app: kubernetes-dashboard addonmanager.kubernetes.io/mode: Reconcile name: kubernetes-dashboard namespace: kube-system --- kind: ClusterRoleBinding apiVersion: rbac.authorization.k8s.io/v1beta1 metadata: name: kubernetes-dashboard-minimal namespace: kube-system labels: k8s-app: kubernetes-dashboard addonmanager.kubernetes.io/mode: Reconcile roleRef: apiGroup: rbac.authorization.k8s.io kind: ClusterRole name: cluster-admin subjects: - kind: ServiceAccount name: kubernetes-dashboard namespace: kube-system # vim dashboard-service.yaml apiVersion: v1 kind: Service metadata: name: kubernetes-dashboard namespace: kube-system labels: k8s-app: kubernetes-dashboard kubernetes.io/cluster-service: "true" addonmanager.kubernetes.io/mode: Reconcile spec: type: NodePort selector: k8s-app: kubernetes-dashboard ports: - port: 80 targetPort: 9090
创建
# kubectl create -f dashboard-rbac.yaml # kubectl create -f dashboard-deployment.yaml # kubectl create -f dashboard-service.yaml
等待数分钟，查看资源状态
# kubectl get all -n kube-system NAME READY STATUS RESTARTS AGE pod/kubernetes-dashboard-68ff5fcd99-5rtv7 1/1 Running 1 27d NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE service/kubernetes-dashboard NodePort 10.0.0.100 <none> 443:30000/TCP 27d NAME DESIRED CURRENT UP-TO-DATE AVAILABLE AGE deployment.apps/kubernetes-dashboard 1 1 1 1 27d NAME DESIRED CURRENT READY AGE replicaset.apps/kubernetes-dashboard-68ff5fcd99 1 1 1 27d
查看访问端口
# kubectl get svc -n kube-system NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE kubernetes-dashboard NodePort 10.0.0.100 <none> 443:30000/TCP 27d
打开浏览器，输入：http://192.168.26.136:30000
如果你的页面没有图表，这个需要安装heapster，后面会讲到。
0x0A 小结
搭建集群入门比较难，概念比较多，可以先了解一下集群的基本知识和各个组件的作用，熟能生巧，多多练习。
1.最好按照我的配置，先跑通再变通
2.有问题先查日志，再谷歌
3.多思考，多梳理逻辑
4.配置文件较多，有很多字段你可能都不知道干啥，不要着急，随着一步步使用，慢慢就熟悉了
本篇文章来自李振良老师的专栏，如果你觉得不错可以订阅支持原版。
